GlaxoSmithKline and Human Genome Sciences receive positive opinion in Europe from the CHMP for Benlysta® belimumab

Issued: London UK and Rockville, Maryland

GlaxoSmithKline (GSK) and Human Genome Sciences, Inc. (Nasdaq: HGSI) announced today that the European Medicines Agency’s Committee for Medicinal Products for Human Use (CHMP) has issued a positive opinion, recommending marketing authorisation for Benlysta^® (belimumab) as an add-on therapy in adult patients with active autoantibody-positive systemic lupus erythematosus, with a high degree of disease activity (e.g. positive anti-dsDNA and low complement), despite standard therapy.

The CHMP is responsible for conducting the assessment of medicines for which an EU-wide marketing authorisation is sought.  As part of its assessment to determine whether or not belimumab meets the necessary quality, safety and efficacy requirements, the CHMP reviewed data from two pivotal Phase 3 studies of belimumab (BLISS-52 and BLISS-76), which enrolled nearly 1700 adult patients with autoantibody-positive active systemic lupus erythematosus.  The final decision regarding approval rests with the European Commission; this decision is normally issued approximately two-to-three months after the CHMP opinion.

“A positive recommendation from the CHMP is a major milestone in the clinical development programme for Benlysta.  We look forward to the final decision from the European Commission regarding marketing authorisation and hope to bring this new medicine to appropriate patients in Europe,” said Moncef Slaoui, Ph.D., Chairman, GSK Research and Development.

H. Thomas Watkins, President and Chief Executive Officer, HGS, said, “We and GSK are committed to making Benlysta available in countries worldwide.  We are well along in building our own HGS commercialisation team in Europe and, assuming a positive European Commission decision, we look forward to working alongside GSK to make Benlysta available to patients.”

About  Benlysta  (belimumab)

Belimumab is the first in a new class of drugs called BLyS-specific inhibitors. Belimumab received approval from the U.S. Food and Drug Administration (FDA) on 9^th March, 2011.  Regulatory applications have been submitted and are currently under review in Canada, Australia, Switzerland, Russia, Brazil, The Philippines, Israel and Colombia.

HGS Conference Call

HGS management will hold a conference call to discuss this announcement this morning at 8:15 AM Eastern.  Investors may listen to the call by dialing 888-455-2265 or 719-457-2601, passcode 9676021, five to 10 minutes before the start of the call.  A replay of the conference call will be available within a few hours after the call ends. Investors may listen to the replay by dialing 888-203-1112 or 719-457-0820, confirmation code 9676021.  Today’s conference call also will be webcast and can be accessed at www.hgsi.com. It is recommended that investors interested in listening to the live webcast log on before the conference call begins to download any software required. Both the audio replay and the archive of the conference call webcast will remain available for several days.

About the GSK/HGS collaboration

GSK and HGS are developing belimumab under a definitive co-development and co-commercialisation agreement entered into in 2006.  Under the agreement, HGS had responsibility for conducting the belimumab Phase 3 trials, with assistance from GSK. The companies share equally in Phase 3/4 development costs, sales and marketing expenses, and profits of any product commercialised under the current agreement.

GlaxoSmithKline – one of the world’s leading research-based pharmaceutical and healthcare companies – is committed to improving the quality of human life by enabling people to do more, feel better and live longer.  For further information please visit www.gsk.com  

GSK Biopharm R&D is employing novel approaches to harness the therapeutic potential of biopharmaceuticals for the benefit of patients with serious autoimmune disease.  

Human Genome Sciences exists to place new therapies into the hands of those battling serious disease.  For more information about HGS, please visit the Company’s web site at www.hgsi.com. HGS, Human Genome Sciences and BENLYSTA are trademarks of Human Genome Sciences, Inc. Other trademarks referenced are the property of their respective owners.

GlaxoSmithKline cautionary statement regarding forward-looking statements
Under the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995, GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Factors that may affect GSK's operations are described under 'Risk Factors' in the 'Business Review' in the company's Annual Report on Form 20-F for 2010.

HGS Safe Harbor Statement

This announcement includes statements that are forward-looking within the meaning of the Private Securities Litigation Reform Act of 1995.  These forward-looking statements include those regarding our expectations for BENLYSTA and for a European regulatory decision regarding BENLYSTA.  These forward-looking statements are based on our current intentions, beliefs and expectations regarding future events. We cannot guarantee that any forward-looking statement will be accurate. Investors should realize that if underlying assumptions prove inaccurate or unknown risks or uncertainties materialize, actual results could differ materially from our expectations. Investors are, therefore, cautioned not to place undue reliance on any forward-looking statement. Any forward-looking statement speaks only as of the date of this announcement, and, except as required by law, we do not undertake to update any forward-looking statement to reflect new information, events or circumstances. Some important factors that could cause our actual results to differ from our expectations in these forward-looking statements include: the occurrence of adverse safety events with BENLYSTA; the inherent uncertainty of the timing and success of regulatory approvals; the ability to manufacture in compliance with regulatory requirements; and our dependence on collaborations over which we may not always have full control. The foregoing list sets forth many, but not all, of the factors that could cause actual results to differ from our expectations in any forward-looking statement.  Investors should consider this cautionary statement, as well as the risk factors identified in our periodic reports filed with the SEC, when evaluating our forward-looking statements.